/etc/profile:此文件为系统的每个用户设置环境信息，当用户第一次登录时,该文件被执行，并从/etc/profile.d目录的配置文件中搜集shell的设置。
/etc/bashrc:为每一个运行bash shell的用户执行此文件.当bash shell被打开时,该文件被读取。
~/.bash_profile:每个用户都可使用该文件输入专用于自己使用的shell信息,当用户登录时,该文件仅仅执行一次!默认情况下,他设置一些环境变量,执行用户的.bashrc文件。
~/.bashrc:该文件包含专用于你的bash shell的bash信息，当登录时以及每次打开新的shell时，该文件被读取。
~/.bash_logout:当每次退出系统(退出bash shell)时，执行该文件。
另外,/etc/profile中设定的变量(全局)的可以作用于任何用户,而~/.bashrc等中设定的变量(局部)只能继承/etc/profile中的变量,他们是"父子"关系。
~/.bash_profile 是交互式、login 方式进入 bash 运行的
~/.bashrc 是交互式 non-login 方式进入 bash 运行的
通常二者设置大致相同，所以通常前者会调用后者。
[yangkai@admin ~]$ cat .
./ .bash_history .bash_profile .mozilla/ .Xauthority
../ .bash_logout .bashrc .viminfo .zshrc
[yangkai@admin ~]$ cat .bashrc
# .bashrc
# Source global definitions
if [ -f /etc/bashrc ]; then
. /etc/bashrc
fi
# User specific aliases and functions
[yangkai@admin ~]$ cat .bash_profile
# .bash_profile
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
. ~/.bashrc
fi
# User specific environment and startup programs
PATH=$PATH:$HOME/bin
export PATH
#echo "hello,kaige."
echo 'hello,kaige!this is 132.'
sleep 1
[yangkai@admin ~]$ cat .bash_logout
# ~/.bash_logout
/usr/bin/clear
echo 'bye,kaige!'
[yangkai@admin ~]$
[yangkai@admin ~]$ cat /etc/bashrc
# /etc/bashrc
# System wide functions and aliases
# Environment stuff goes in /etc/profile
# By default, we want this to get set.
# Even for non-interactive, non-login shells.
if [ $UID -gt 99 ] && [ "`id -gn`" = "`id -un`" ]; then
umask 002
else
umask 022
fi
# are we an interactive shell?
if [ "$PS1" ]; then
case $TERM in
xterm*)
if [ -e /etc/sysconfig/bash-prompt-xterm ]; then
PROMPT_COMMAND=/etc/sysconfig/bash-prompt-xterm
else
PROMPT_COMMAND='echo -ne " 33]0;${USER}@${hostname%%.*}:${PWD/#$HOME/~}"; echo -ne " 07"'
fi
;;
screen)
if [ -e /etc/sysconfig/bash-prompt-screen ]; then
PROMPT_COMMAND=/etc/sysconfig/bash-prompt-screen
else
PROMPT_COMMAND='echo -ne " 33_${USER}@${HOSTNAME%%.*}:${PWD/#$HOME/~}"; echo -ne " 33"'
fi
;;
*)
[ -e /etc/sysconfig/bash-prompt-default ] && PROMPT_COMMAND=/etc/sysconfig/bash-prompt-default
;;
esac
# Turn on checkwinsize
shopt -s checkwinsize
[ "$PS1" = "s-v$ " ] && PS1="[u@h W]$ "
fi
if ! shopt -q login_shell ; then # We're not a login shell
# Need to redefine pathmunge, it get's undefined at the end of /etc/profile
pathmunge () {
if ! echo $PATH | /bin/egrep -q "(^|:)$1($|:)" ; then
if [ "$2" = "after" ] ; then
PATH=$PATH:$1
else
PATH=$1:$PATH
fi
fi
}
# Only display echos from profile.d scripts if we are no login shell
# and interactive - otherwise just process them to set envvars
for i in /etc/profile.d/*.sh; do
if [ -r "$i" ]; then
if [ "$PS1" ]; then
. $i
else
. $i >/dev/null 2>&1
fi
fi
done
unset i
unset pathmunge
fi
# vim:ts=4:sw=4
[yangkai@admin ~]$